Projecting device

ABSTRACT

A projecting device includes a projector configured to project a projection image including a content image onto a projection surface; detectors configured to detect a target position at which the content image is to be projected; an image processor configured to generate the projection image; a driver configured to change an orientation of the projector in order to change a projection position of the projection image; and a controller configured to control the image processor to set a position of the content image included in the projection image in order to minimize a difference between a display position of the content image and the target position when an optical axis of the projector is orthogonal to the projection surface, and control the driver to set the orientation of the projector in order to project the projection image at the target position on the projection surface.

BACKGROUND

1. Technical Field

The present disclosure relates to a projecting device which detects apredetermined target and projects a video while following the detectedtarget.

2. Related Art

In recent years, as a method of sending information aboutadvertisements, guides and the like to a moving person, an advertisingmethod (i.e., a digital signage) using a display device such as a liquidcrystal display device or a projector becomes popular. Furthermore,there is also studied and developed a liquid crystal display device fordetecting a moving person and individually displaying information to thedetected person (for example, see JP 2005-115270 A and JP 2012-118121A).

JP 2005-115270 A discloses a display device for moving body additionalinformation including a video camera for imaging a moving body passingthrough a wall surface or a floor surface having an inside of a certainframe as a background, an image processor for sequentially extractingpositional coordinates of the moving body entering an inner part of acurrent image picked up sequentially by means of the video camera,calculating, based on the extracted positional coordinates, respectivepositional coordinates for display which are placed apart from thepositional coordinates, sequentially inserting information of texts,images and the like in a predetermined display size into the respectivecalculated positional coordinates for display, and outputting theinformation as video information, and a video display device having adisplay screen on a wall surface or a floor surface and serving todisplay video information such as texts, images and the like in thepredetermined display sizes on the display screen in accordance with themovement of the moving body. According to the display device, it ispossible to recognize a moving body (e.g., a person) by means of thevideo camera and to individually display information for the recognizedmoving body.

As a video display device of this type, a display or a projector isused. In the case in which a wide range is covered with a single videodisplay device, the projector is used to project a video onto aprojection surface while changing a projecting direction. In this case,a focused range is reduced on the projection surface depending on aprojecting direction of the image projected from the projecting device.Consequently, only a part of the projection image (a projection region)is focused in some cases.

SUMMARY

The present disclosure provides a projecting device capable of enlarginga focus scope where a focused projection image is obtained when a videois to be projected onto a projection surface.

According to one aspect of the present disclosure, a projecting deviceis provided. The projecting device includes a projector configured toproject a projection image including a content image onto a projectionsurface, a first detector configured to detect a target position on theprojection surface at which the content image is to be projected, animage processor configured to generate the projection image, a driverconfigured to change an orientation of the projector in order to changethe projection position of the projection image, and a controllerconfigured to control the image processor and the driver. The controllercontrols the image processor to set the position of the content imageincluded in the projection image in order to minimize a differencebetween a display position and a target position on the projectionsurface of the content image when the projection image is projected in astate in which the orientation of the projector is set such that theoptical axis of the projector is orthogonal to the projection surface,and controls the driver to set the orientation of the projector in orderto project, at the target position on the projection surface, theprojection image including the content image at the set position.

According to the present disclosure, in the case in which a video isprojected onto the projection surface, it is possible to enlarge a focusscope where a focused projection image is obtained.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram showing a situation in which a projectordevice projects a video onto a wall surface.

FIG. 2 is a schematic diagram showing a situation in which the projectordevice projects a video onto a floor surface.

FIG. 3 is a block diagram showing an electrical structure of theprojector device.

FIG. 4 is an explanatory view showing an example of utilization of theprojector device.

FIG. 5 is a block diagram showing a functional structure of a controllerof the projector device (a first embodiment).

FIGS. 6A, 6B and 6C are views for explaining control of a position of acontent image in a projection image through the controller of theprojector device (in the case in which a target projection position isplaced out of a range of the projection image in a state in which anoptical axis of the projector device is orthogonal to a projectionsurface).

FIG. 7 is a view for explaining focus distance calculation through thecontroller of the projector device.

FIGS. 8A and 8B are views for explaining the control of the position ofthe content image included in the projection image through thecontroller of the projector device (in the case in which the targetprojection position is placed within the range of the projection imagein the state in which the optical axis of the projector device isorthogonal to the projection surface).

FIGS. 9A and 9B are views showing a focus scope on the projectionsurface through projection control of a projector device 100 accordingto the present embodiment.

FIGS. 10A and 10B are views showing a focus scope on the projectionsurface through the projection control of the projector device 100according to a comparative example.

FIG. 11 is a block diagram showing a functional structure of acontroller of a projector device (a second embodiment).

FIG. 12 is a block diagram showing a functional structure of acontroller of a projector device (a third embodiment).

FIG. 13A is a view showing information on a display size of a contentimage and FIG. 13B is a view showing information on a display shape ofthe content image (a fourth embodiment).

FIG. 14 is a block diagram showing a functional structure of acontroller of a projector device (a fifth embodiment).

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

Embodiments will be described below in detail with reference to thedrawings. In some cases, however, unnecessary detailed description willbe omitted. For example, detailed description of well-known matters orrepetitive description of substantially identical structures will beomitted in some cases. The reason is that unnecessary redundancy of thefollowing description is to be avoided and a person skilled in the artis to be enabled to make easy understanding.

The inventor(s) provide(s) the accompanying drawings and the followingdescription for allowing a person skilled in the art to fully understandthe present disclosure and it is not intended that the subject describedin claims should be thereby restricted to the accompanying drawings andthe following description.

First Embodiment

A first embodiment will be described with reference to the accompanyingdrawings. In the following, description will be given of a projectordevice as a specific embodiment of a projecting device according to thepresent disclosure.

[1-1. Outline]

With reference to FIGS. 1 and 2, the outline of a projecting operationto be performed by the projector device 100 will be described. FIG. 1 isan image view of the projector device 100 projecting a video onto a wall140. FIG. 2 is an image view of the projector device 100 projecting avideo onto a floor surface 150.

As shown in FIGS. 1 and 2, the projector device 100 is fixed to ahousing 120 together with a driver 110. A wiring connected electricallyto each component of a body 100 b of the projector device and the driver110 is connected to a power supply through the housing 120 and a wiringduct 130. Consequently, power is supplied to the body 100 b of theprojector device 100 and the driver 110. The projector device 100 has anopening 101 formed in the body 100 b. The projector device 100 projectsa video through the opening 101.

The driver 110 can drive the projector device 100 to change a projectingdirection of the projector device 100 (in other words, to change anorientation, that is, a posture of the body 100 b of the projectordevice). The driver 110 can drive the projector device 100 to set theprojecting direction of the projector device 100 to a direction of thewall 140 as shown in FIG. 1. Thus, the projector device 100 can projecta video 141 onto the wall 140. Similarly, the driver 110 can drive theprojector device 100 to change the projecting direction of the projectordevice 100 to a direction of the floor surface 150 as shown in FIG. 2.Thus, the projector device 100 can project a video 151 onto the floorsurface 150. The driver 110 may drive the projector device 100 based ona manual operation of a user or may automatically drive the projectordevice 100 depending on a result of detection obtained by apredetermined sensor. Moreover, the video 141 to be projected onto thewall 140 and the video 151 to be projected onto the floor surface 150may be different in contents from each other or may be identical incontents to each other. The driver 110 includes an electric motor. Thedriver 110 turns the body 100 b of the projector device 100 in ahorizontal direction (a pan direction) and a vertical direction (a tiltdirection) to change the orientation (posture) of the projector device100. Thus, the driver 110 can change the projecting direction of thevideo, that is, a projection position of the video.

The projector device 100 can detect a specific object and project avideo (a content) at a position or in a region having a predeterminedpositional relationship with a position of the specific object set to bea reference while following the movement of the detected object. In thefollowing description, the projector device 100 detects a “person” asthe specific object and projects a video while following the movement ofthe detected person.

[1-2. Structure]

The structure and operation of the projector device 100 will bedescribed below in detail.

FIG. 3 is a block diagram showing the electrical structure of theprojector device 100. The projector device 100 includes a drivingcontroller 200, a light source 300, a video generator 400, and aprojection optical system 500. Moreover, the projector device 100includes the driver 110 and an image processor 160. The structure ofeach component of the projector device 100 will be described below inorder.

The driving controller 200 includes a controller 210, a memory 220, anda distance detector 230.

The controller 210 is a semiconductor device which controls the wholeprojector device 100. In other words, the controller 210 controls theoperations of the respective components (the distance detector 230, thememory 220) of the driving controller 200, the light source 300, thevideo generator 400, and the projection optical system 500. Moreover,the controller 210 controls the image processor 160 in order to change adisplay position of a content image within a projection angle of view ofthe projection light from the projector device 100 (i.e., a position ofthe content image in a projection image on the projection surface). Thecontroller 210 also controls the driver 110 in order to change aprojecting direction of the projection light from the projector device100 (i.e., a projection position of the projection image). Moreover, thecontroller 210 performs focus control of the projection image. Thecontroller 210 may be configured with only hardware or may beimplemented by combining hardware with software. For example, thecontroller 210 can be configured with at least one CPU, MPU, GPU, ASIC,FPGA, DSP or the like.

The memory 220 is a storage element which stores various kinds ofinformation. The memory 220 is configured with a flash memory, aferroelectric memory, or the like. The memory 220 stores, for example, acontrol program for controlling the projector device 100. Moreover, thememory 220 stores various kinds of information supplied from thecontroller 210. Furthermore, the memory 220 stores data (a still image,a moving image) on a content image to be projected, a reference tableincluding setting of a display size of the content image, positioninformation and a projection angle of view of the projector device 100,distance information from the projector device 100 to the projectionsurface, and the like, data on a shape of a target object for objectdetection, and the like.

The distance detector 230 is configured with a distance image sensor of,for example, a TOF (Time-of-Flight) type (hereinafter, such a sensorwill be referred to as a TOF sensor) and linearly detects a distancefrom the distance detector 230 to an opposed projection surface orobject. When the distance detector 230 is opposed to the wall 140, thedistance detector 230 detects a distance from the distance detector 230to the wall 140. If a picture is suspended and hung on the wall 140, thedistance detector 230 can also detect a distance from the distancedetector 230 to an opposed surface of the picture. When the distancedetector 230 is opposed to the floor surface 150, similarly, thedistance detector 230 detects a distance from the distance detector 230to the floor surface 150. If an object is mounted on the floor surface150, the distance detector 230 can also detect a distance from thedistance detector 230 to an opposed surface of the object. The distancedetector 230 may be a sensor using infrared rays or a sensor usingvisible light.

The controller 210 can detect a projection surface (e.g., the wall 140,the floor surface 150) or a specific object (e.g., a person, an article)based on distance information supplied from the distance detector 230.

Although the TOF sensor has been described above as an example of thedistance detector 230, the present disclosure is not restricted thereto.In other words, a known pattern such as a random dot pattern may beprojected to calculate a distance from a displacement of the pattern, ora parallax generated by a stereo camera may be utilized. Moreover, theprojector device 100 may include an RGB camera (not shown) together withthe distance detector 230 (TOF). In that case, the projector device 100may detect the object by using image information to be output from theRGB camera together with the distance information to be output from theTOF sensor. By using the RGB camera together, it is possible to detectthe object by utilizing information such as a color possessed by theobject or a character described on the object in addition to informationabout a three-dimensional shape of the object obtained from the distanceinformation.

The image processor 160 is an image processing circuit configured with,for example, an ASIC. The image processor 160 may be configured with asingle circuit together with the controller 210. The image processor 160generates a projection image including a content image from the memory220. The image processor 160 changes a display position of the contentimage at the projection angle of view of the projector device 100 (i.e.,a position of the content image included in the projection image on theprojection surface) by the control of the controller 210. Moreover, theimage processor 160 performs geometric correction for the projectionimage based on the projection position of the projection image.

Subsequently, an optical structure of the projector device 100 will bedescribed. More specifically, description will be given of thestructures of the light source 300, the video generator 400, and theprojection optical system 500 in the projector device 100.

The light source 300 supplies light necessary for generating aprojection video to the video generator 400. For example, the lightsource 300 may be configured with a semiconductor laser, a dichroicmirror, a λ/4 plate, a phosphor wheel, or the like.

The video generator 400 generates a projection video obtained byspatially modulating light incident from the light source 300 inresponse to a video signal indicative of a projection image to begenerated by the image processor 160 and supplied through the controller210, and supplies the projection video to the projection optical system500. For example, it is sufficient that the video generator 400 isconfigured with a DMD (Digital-Mirror-Device) or the like. In place of aDLP (Digital-Light-Processing) method using the DMD, it is also possibleto employ a liquid crystal method.

The projection optical system 500 performs optical conversion such asfocusing or zooming on the video supplied from the video generator 400.The projection optical system 500 is opposed to the opening 101 and avideo is projected through the opening 101. The projection opticalsystem 500 includes optical members such as a zoom lens and a focuslens. The projection optical system 500 enlarges light advancing fromthe video generator 400 and projects the enlarged light onto theprojection surface. The controller 210 can control the projection regionwith respect to the projecting target to have a desirable zoom value byadjusting the position of the zoom lens. Moreover, the controller 210can focus on a projection video by adjusting the position of the focuslens.

[1-3. Operation]

The operation of the projector device 100 having the above structurewill be described below. The projector device 100 according to thepresent embodiment can detect a person as a specific object, follow themovement of the detected person, and project a predetermined video at aposition having a predetermined positional relationship with a positionof the person (for example, a position placed 1 m before the position ofthe detected person in the advancing direction).

Specifically, the distance detector 230 emits infrared detection lighttoward a certain region (e.g., an entrance of a store or a building) andacquires distance information in the region. The controller 210 detectsa person, a position of the person, an advancing direction, and thelike, based on the distance information acquired by the distancedetector 230 (the advancing direction is detected from distanceinformation in a plurality of frames). The controller 210 determines atarget projection position at which a projection image is to beprojected (e.g., a position placed 1 m before the position of thedetected person in the advancing direction) based on the position, theadvancing direction, or the like of the detected person. Then, thecontroller 210 controls the image processor 160 to determine a positionof a content image in the projection image so as to project the contentimage at the target projection position. Further, the controller 210controls the driver 110 to move the body of the projector device 100 inthe pan direction or the tilt direction if necessary. The controller 210detects the position of the person every predetermined period (e.g.,1/60 seconds) and projects a video to cause the projection image tofollow the person, based on the position of the detected person.

For example, as shown in FIG. 4, the projector device 100 is provided ona passageway in a building, a ceiling or a wall of a hall, or the like,and follows the movement of a person 6 to project a projection image 8when detecting the person 6. The projection image (content image) 8includes a graphic (an arrow or the like) or a message for leading orguiding the person 6 to a predetermined place or store, a message forwelcoming the person 6, an advertising text, an image for directing themovement of the person 6 such as a red carpet, and the like. Theprojection image 8 may be a still image or a moving image. Consequently,desirable information can be presented to a position where the detectedperson 6 can always see the desirable information easily depending onthe movement of the detected person 6. Thus, the desirable informationcan be passed to the person 6 reliably.

The operation of the projector device 100 will be described below indetail. FIG. 5 is a diagram showing a functional structure of thecontroller 210. In the following description, a position is atwo-dimensional vector having a size and a direction.

The human position detector 11 detects a person based on distanceinformation (a distance image) sent from the distance detector 230. Theperson is detected by previously storing a feature value indicative ofthe person in the memory 220 and detecting an object indicative of thefeature value from the distance information (a distance image). Thehuman position detector 11 further calculates a position (a relativeposition) of the detected person. Herein, the “relative position”represents a position in a coordinate system with the position of thedriver 110 set to be a center. A target projection position calculationunit 13 calculates a target projection position (a relative position) ofthe projection image on the basis of the position of the detectedperson. For example, a position placed apart from the position of thedetected person by a predetermined distance (e.g., 1 m) in the advancingdirection is calculated as the target projection position.

In order to project the content image at the target projection position,a shift direction calculation unit 21, a shift amount calculation unit23, and a display position determination unit 25 adjust the position ofthe content image included in the projection image and a projectingdirection calculation unit 31 adjusts an adjustment shortage by a changein the projecting direction of the projector device 100 (i.e., theprojection position of the projection image).

FIGS. 6A to 6C are views for explaining the control of the position ofthe content image included in the projection image. Fig. 6A is a viewshowing the projector device 100 and the projection surface 151 seenlaterally, and FIGS. 6B and 60 are views showing the projection surface151 seen from the projector device 100 side. As shown in FIG. 6A, theprojector device 100 is set to such an orientation that an optical axis172 thereof is basically orthogonal to the projection surface 151. Asshown in FIG. 6B, moreover, a projection image R1 to be projected by theprojector device 100 includes a content image 180, and the content image180 is set to be basically positioned on a center of the projectionimage R1 (at a position where an intersection point 173 of the opticalaxis 172 and the projection surface 151 is set to be a center).

The projector device 100 shifts the position of the content image 180included in the projection image R1 and the projecting direction of theprojector device 100 depending on a target projection position 175 (atarget projection region 174) from the basic state. In other words, asshown in FIGS. 6A and 6B, the shift direction calculation unit 21, theshift amount calculation unit 23, and the display position determinationunit 25 control the image processor 160 to shift the position of thecontent image included in the projection image R1 (at a projection angleof view θ) when the projection position of the content image 180 to beprojected in a state in which the optical axis 172 of the projectordevice 100 is orthogonal to the projection surface 151 is not coincidentwith the target projection position 175 (e.g., the central position ofthe target projection region 174). When the position of the contentimage 180 is not coincident with the target projection position 175,then, the projecting direction calculation unit 31 controls the driver110 to change the projecting direction of the projector device 100,thereby causing the position of the content image 180 to be coincidentwith the target projection position 175.

More specifically, the shift direction calculation unit 21 calculatesthe shift direction in the position of the content image included in theprojection image R1. As shown in FIG. 6A, specifically, the shiftdirection calculation unit 21 obtains the intersection point (i.e., therelative position) 173 of the optical axis 172 and the projectionsurface 151 in a state in which the orientation of the projector device100 is set such that the optical axis 172 of the projector device 100 isorthogonal to the projection surface 151. As shown in FIG. 6C, then, theshift direction calculation unit 21 obtains a direction from theposition of the intersection point 173 toward the target projectionposition 175 (e.g., the central position of the target projection region174) on the projection surface 151 (e.g., a direction shown with anarrow in FIG. 6C) as a shift direction of the position of the contentimage 180 included in the projection image R1.

The shift amount calculation unit 23 calculates a shift amount of thecontent image included in the projection image R1. Specifically, theshift amount calculation unit 23 obtains a range of the projection imageR1 in the projection surface 151 based on information about theprojection angle of view θ and a distance from the projector device 100to the projection surface 151, the information being stored in thememory 220. Then, the shift amount calculation unit 23 obtains a shiftamount (e.g., the distance from the position 173 to the central portionof the content image 180) such that the content image 180 is positionedin a most end of the projection image R1 in the shift direction, inconsideration of information about the display size of the content imagestored in the memory 220 (e.g., a value in an X direction and a value ina Y direction of a rectangular shape) (see FIG. 6C).

The display position determination unit 25 determines the position ofthe content image included in the projection image R1 (e.g., the centralposition of the content image) from the position 173, the obtained shiftdirection, and the obtained shift amount.

The image processor 160 receives the position of the content image 180included in the projection image R1 from the display positiondetermination unit 25 and disposes the content image 180 in theprojection image R1, based on the position.

In the case in which the content image 180 does not reach the targetprojection position 175 even if the position of the content image 180 isshifted at a maximum within the projection image R1, furthermore, theorientation of the projector device 100 is changed such that the contentimage 180 is projected at the target projection position 175. For thispurpose, the projecting direction calculation unit 31 calculates theprojecting direction of the projection image R1 projected by theprojector device 100 (i.e., the orientation of the projector device100). Specifically, the projecting direction calculation unit 31 obtainsthe projecting direction of the projector device 100 in which thedisplay position (e.g., the central position) determined by the displayposition determination unit 25 and the target projection position (e.g.,the central position) are caused to be coincident with each other, basedon a difference between these positions. Thereafter, the projectingdirection calculation unit 31 calculates a driving command (a drivingvoltage) for driving the driver 110 to turn the projector device 100into the obtained projecting direction.

The driver 110 changes the projecting direction of the projector device100 based on the driving command given from the projecting directioncalculation unit 31. At this time, the image processor 160 performsgeometric correction processing for the content image 180 correspondingto the target projection position 175.

Next, it is necessary to perform focusing at the target projectionposition 175. For this purpose, the focus distance calculation unit 41obtains a focus distance. FIG. 7 is a view for explaining the focusdistance calculation. FIG. 7 is a view showing the projector device 100and the projection surface 151 seen laterally. As shown in FIG. 7, thefocus distance calculation unit 41 assumes a virtual projection surface176 of the projector device 100 to obtain a distance between the virtualprojection surface 176 and the projector device 100 as a focus distanceLf. The virtual projection surface 176 is a plane which sets an opticalaxis 177 of the projector device 100 as a normal and passes through thetarget projection position 175.

Specifically, the focus distance calculation unit 41 calculates aprojection distance L1 between the position of the projector device 100and the target projection position 175 (the target projection region174). Then, the focus distance calculation unit 41 calculates the focusdistance Lf based on the projection distance L1 from the projectordevice 100 to the target projection position 175 and an angle for ed bythe optical axis 177 of the projector device 100 and the direction ofthe content image 180 seen from the projector device 100. Herein, thetarget projection position 175 is placed at the most end at theprojection angle of view θ. Therefore, an angle a formed by a straightline 178 connecting the position of the projector device 100 and thetarget projection position 175 and the optical axis 177 is obtained froma half of the projection angle of view θ and the target projectionposition 175 in the projection image R1. Consequently, the focusdistance calculation unit 41 calculates the focus distance Lf of theprojector device 100 from the projection distance L1 and the angle a.

The focus control unit 43 calculates a driving command (a drivingvoltage) for driving a driver for a focus lens such that the focusdistance of the focus lens of the projection optical system 500 is equalto the focus distance Lf obtained by the focus distance calculation unit41.

The projection optical system 500 drives the focus lens driver based onthe driving command given from the focus control unit 43 and focuses onthe displayed content image.

As shown in FIGS. 8A and 8B, in the case in which the target projectionposition 175 is within the range of the projection region R1 in a statein which the orientation of the projector device 100 is set such thatthe optical axis 172 of the projector device 100 is orthogonal to theprojection surface 151, the orientation of the projector device 100 isprevented from being further changed. In other words, the shift amountcalculation unit 23 calculates, as a shift amount, a distance from theintersection point 173 of the optical axis 172 of the projector device100 and the projection surface 151 to the target projection position 175(the central position of the target projection region 174). Based on theshift amount, the display position determination unit 25 determines theposition of the content image 180 of the projection image R1 as thetarget projection position 175 (the target projection region 174). Atthis time, the content image 180 is displayed at the target projectionposition 175 in a state in which the optical axis 172 of the projectordevice 100 is orthogonal to the projection surface 151. For this reason,a change amount in the projecting direction of the projector device 100,which is obtained by the projecting direction calculation unit 31, iszero. Consequently, it is possible to project the content image 180 atthe target projection position 175 (within the projection region 174)without changing the projecting direction of the projector device 100.Therefore, focusing can be performed in the whole projection image R1.

As described above, the projector device 100 according to the presentembodiment first shifts the position of the content image 180 includedin the projection image R1 such that the content image 180 is displayedin a position which is as close to the target projection position 175 aspossible when an image is projected in a state in which the optical axis172 of the projector device 100 is orthogonal to the projection surface151 (FIGS. 6A to 6C). In the case in which the content image 180 cannotbe displayed at the target projection position 175 by adjustment of theposition of the content image 180 included in the projection image R1,the content image 180 is displayed at the target projection position 175by a further change in the orientation of the projector device 100.Thus, description will be given of an advantageous effect of controllingthe projection image R1 (the projection region R2 after the geometriccorrection) and the projection position thereof.

FIGS. 9A and 9B are views showing a focus scope on the projectionsurface through the projection control of the projector device 100according to the present embodiment. On the other hand, FIGS. 10A and10B are views showing a focus scope on the projection surface throughthe projection control of the projector device 100 according to acomparative example. FIGS. 9A and 10A are views showing the projectordevice 100 and the projection surface 151 seen laterally. FIGS. 9B and10B are views showing the projection surface 151 seen from the projectordevice 100 side.

In the comparative example shown in FIGS. 10A and 10B, the position ofthe content image 180 included in the projection image R2 (after thegeometric correction) is maintained in the central position of theprojection image R2 and the projecting direction of the projector device100 is changed to be turned toward the target projection position 175 toproject the content image 180 at the target projection position 175. Atthis time, in the case in which the content image 180 is focused on,that is, in the case in which the optical axis 177 of the projectordevice 100 is set to be a normal and the virtual projection surface 176passing through the target projection position 176 is focused, thedistance between the virtual projection surface 176 and the projectordevice 100 is equal to the focus distance Lf and focusing is performedin a predetermined focusing depth D corresponding to the focus distanceLf. For this reason, there is performed focusing on the image projectedin the range (focus scope) Rf2 corresponding to the focus depth D on theprojection surface 151.

On the other hand, in the present embodiment, the position of thecontent image 180 included in the projection image R2 (after thegeometric correction) is shifted from the central position of theprojection image R2, and the projecting direction of the projectordevice 100 is changed by a difference between the shifted position andthe target projection position 175 to project the content image 180 atthe target projection position 175 as shown in FIGS. 9A and 9B.Consequently, a moving amount in the projecting direction of theprojector device 100 is reduced more greatly so that the image can beprojected in a closer state to the state in which the optical axis 177is orthogonal to the projection surface 151. Therefore, it is possibleto obtain a focus scope Rf1 which is enlarged more greatly as comparedto Rf2 shown in FIG. 10A on the projection surface 151 corresponding tothe predetermined focus depth D.

[1-3. Advantageous Effects]

As described above, in the present embodiment, the projecting device 100includes the projector (the video generator 400 and the projectionoptical system 500) configured to project the projection image R2including the content image 180 (after the geometric correction: theprojection image before the geometric correction is represented by R1)onto the projection surface 151, the first detector (the distancedetector 230 and the human position detector 11) configured to detectthe target projection position 175 on the projection surface 151 atwhich the content image 180 is to be projected, the image processor 160configured to generate the projection image R2, the driver 110configured to change the orientations of the projectors 400 and 500 inorder to change the projection position of the projection image R2, andthe controller 210 configured to control the image processor 160 and thedriver 110. The controller 210 controls the image processor 160 to setthe position of the content image 180 in the projection image such thatthe difference between the display position and the target projectionposition 175 is minimized on the projection surface 151 of the contentimage 180 when the projection image is projected in the state in whichthe orientations of the projectors 400 and 500 are set such that theoptical axis 177 of the projectors 400 and 500 is orthogonal to theprojection surface 151 (i.e., in the state in which the projectors 400and 500 are opposed to the projection surface 151). The controller 210also controls the driver 110 to set the orientations of the projectors400 and 500 such that the projection image R2 including the contentimage 180 at the set position is projected at the target projectionposition 175 on the projection surface 151.

According to the present embodiment, in the case in which an image isprojected onto the projection surface 151, the position of the contentimage included in the projection image R2 on the projection surface 151of the projector device 100 (i.e., the display position of the contentimage 180 at the projection angle of view θ of the projector device 100)is set to the most end of the projection image R2 (i.e., at theprojection angle of view θ), that is, is set such that the differencebetween the display position of the content image and the targetprojection position 175 is minimized, and the projecting direction ofthe projector device 100 is changed corresponding to the differencebetween the display position and the target projection position.Consequently, the moving amount in the projecting direction of theprojector device 100 is reduced so that an image can be projected in acloser state to the state in which the optical axis 177 is orthogonal tothe projection surface 151. Therefore, it is possible to enlarge thefocus scope Rf1 in which the focusing is performed on the projectionsurface 151 corresponding to the to the predetermined focus depth D.

Second Embodiment

In a second embodiment, focus control is performed for focusing on apredetermined position in a content image. For example, in the case inwhich the content image has character information, focusing on aposition of the character information is preferentially performed.

A structure of a projector device according to the second embodiment isbasically the same as that according to the first embodiment describedwith reference to FIGS. 1 to 3, and the function and operation of acontroller 210 are different from those described above.

With reference to FIG. 11, description will be given of a specificoperation of the controller 210 according to the second embodiment. FIG.11 is a view showing a functional structure of the controller 210according to the second embodiment. The controller 210 shown in FIG. 11further includes a preferential position determination unit 45.Information indicative of a position at which in a content imagecharacter information is included (e.g., a relative position with acenter of the content image) is previously stored in the memory 220.

The preferential position determination unit 45 acquires, from thememory 220, the information indicative of the position at which in thecontent image the character information is included, and determines thisposition as a preferential position in which focusing is preferentiallyperformed in the content image.

The operation of the controller 210 according to the present embodimentwill be described below with a position 175 set to be the preferentialposition in FIG. 7. As shown in FIG. 7, a focus distance calculationunit 41 sets an optical axis 177 of the projector device 100 as a normaland assumes a virtual projection surface 176 passing through the targetprojection position 175 to calculate a distance between the virtualprojection surface 176 and the projector device 100 as a focus distanceLf. Specifically, the focus distance calculation unit 41 calculates aprojection distance L1 between the position of the projector device 100and the preferential position 175. Then, the focus distance calculationunit 41 calculates the focus distance Lf based on the projectiondistance L1 from the projector device 100 to the preferential position175 and the angle formed by the optical axis 177 of the projector device100 and the direction of the content image 180 seen from the projectordevice 100. Herein, an angle a foisted by the straight line 178connecting the position of the projector device 100 and the preferentialposition 175 and the optical axis 177 is calculated from the half of theprojection angle of view θ and the preferential position 175 in theprojection image R1. Consequently, the focus distance calculation unit41 calculates the focus distance Lf of the projector device 100 from theprojection distance L1 and the angle α.

By calculating the focus distance Lf as described above, thus, it ispossible to perform focusing into a portion of the content image to beprioritized.

Third Embodiment

In the second embodiment, the preferential position to be preferentiallyfocused in the content image is determined based on the positioninformation previously stored in the memory 220. However, it is alsopossible to detect a position gazed in the content image by a gazer,using a well-known visual line detecting technique and to set thedetected position as a preferential position to be preferentiallyfocused in the content image.

A structure of a projector device according to a third embodiment isbasically the same as that according to the first embodiment describedwith reference to FIGS. 1 to 3 except that a visual line detector isfurther provided. Moreover, the function and operation of a controller210 are different from those described above.

With reference to FIG. 12, description will be given of a structure andan operation of the controller 210 in the projector device 100 accordingto the third embodiment. As shown in FIG. 12, the projector device 100further includes a visual line detector 240 and a preferential positiondetermination unit 45 in addition to the structure according to thefirst embodiment. The visual line detector 240 is an imaging device suchas a camera and detects a gaze direction of eyes of a person to bedetected by the distance detector 230 and the human position detector11.

The preferential position determination unit 45 obtains a gaze positionin a projection surface 151, that is, a gaze position in a content imageprojected onto the projection surface 151, from a position of a persondetected by the distance detector 230 and the human position detector 11and the gaze direction detected by the visual line detector 240, anddetermines the gaze position thus obtained as a preferential position atwhich in the content image focusing is preferentially performed.

Consequently, it is possible to perform focusing on a portion in thecontent image which is being actually seen by a person offering thecontent image.

Fourth Embodiment

In the first embodiment, the display size of the content image 180(e.g., the value in the X direction and the value in the Y direction ofthe rectangular shape) is previously stored in the memory 220 and theshift amount is calculated based on the stored display size. In thepresent embodiment, a binary image indicating a display portion and anon-display portion of the content image 180 by two values is stored inthe memory 220, and the shift amount of the content image 180 isobtained based on a shape of the display portion of the binary image.

Although a structure of a projector device according to the fourthembodiment is basically the same as that according to the firstembodiment described with reference to FIGS. 1 to 3, a function and anoperation of a controller 210 are different from those described above.

With reference to FIG. 11, a specific operation of the controller 210according to the fourth embodiment will be described. FIG. 11 is adiagram showing a functional structure of the controller 210 accordingto the second embodiment. Since the same diagram is also employed in thefourth embodiment, description will be omitted. The memory 220previously stores information about a binary image indicative of thedisplay shape of a content image 180 in place of information indicativeof a display size of the content image 180.

FIG. 13A is a view showing information about the display size of thecontent image 180. FIG. 13B is a view showing information about thedisplay shape of the content image 180. As shown in FIG. 13A, in thefirst embodiment, even if the shape of the content image 180 takes acircular shape, for example, the size of the rectangular shaperepresented by the value “X” in the X direction and the value “Y” in theY direction is stored as the display size of the content image 180 inthe memory 220.

On the other hand, in the present embodiment, the memory 220 stores abinary image representing the display portion “1” and the non-displayportion “0” by two values as the display shape of the content image 180as shown in FIG. 13B. For example, the value “1” indicative display orthe value “0” indicative of non-display is set for every pixel of thecontent image taking the rectangular shape. The display portion “1” inthe binary image indicates the display shape of the content image 180.

A shift amount calculation unit 23 obtains the display shape of thecontent image 180 from the display portion “1” in the binary image, andcalculates the shift amount such that the content image 180 ispositioned in the most end of a projection image R2 based on the displayshape.

Thus, the shift amount is computed based on a closer shape to thedisplay shape of the content image 180. Consequently, the content image180 can be positioned at a more end in the projection image R2 (e.g.,four corner portions of the rectangular shape). Therefore, the focusscope can be enlarged more greatly.

Fifth Embodiment

In the fourth embodiment, the binary image indicating the displayportion and the non-display portion by two values as the display shapeof the content image 180 is stored in the memory 220 and the shiftamount is obtained based on the shape of the display portion of thestored binary image. In a fifth embodiment, a display shape is detectedfrom a content image 180 itself and a shift amount is obtained based onthe detected display shape.

Although a structure of a projector device according to the fifthembodiment is basically the same as that according to the firstembodiment described with reference to FIGS. 1 to 3, a function and anoperation of a controller 210 are different from those described above.

With reference to FIG. 14, a specific operation of the controller 210according to the fifth embodiment will be described. FIG. 14 is adiagram showing a functional structure of the controller 210 accordingto the fifth embodiment. The controller 210 shown in FIG. 14 furtherincludes a display shape detector 27.

The display shape detector 27 detects the content image stored in thememory 220 as a binary image indicating a display portion and anon-display portion by two values. Specifically, the display shapedetector 27 detects as a binary image indicating, by two values, a pixelhaving a predetermined color in the content image as the non-displayportion “0” and a pixel having a color other than the predeterminedcolor in the content image as the display portion “1” based on a chromacolor, for example. The shift amount calculation unit 23 obtains thedisplay shape of the content image 180 from the display portion “1” inthe detected binary image, and calculates the shift amount such that thecontent image 180 is positioned at the most end of the projection imageR2, based on the display shape.

Also in the fifth embodiment, in the same manner as in the fourthembodiment, the shift amount is calculated based on a closer shape tothe display shape of the content image 180. Consequently, the contentimage 180 can be positioned at a more end in the projection image R2. Asa result, the focus scope can be enlarged more greatly.

Other Embodiments

The first to fifth embodiments have been described above as an exampleof the technique to be disclosed in the present application. Thetechnique in the present disclosure is not restricted to the first tofifth embodiments, but can also be applied to embodiments in whichchange, replacement, addition, and omission are properly performed.Moreover, it is also possible to make a new embodiment by combining therespective components described in the first to fifth embodiments.Therefore, other exemplary embodiments will be described below.

(1) The projector device 100 in the present disclosure is an example ofa projecting device. Each of the distance detector 230 and the humanposition detector 11 in the present disclosure is an example of adetector that detects a target projection position on a projectionsurface at which a content image is to be projected. Each of the videogenerator 400 and the projection optical system 500 in the presentdisclosure is an example of a projector.

(2) Although a person is detected as a specific object and apredetermined image (content) is displayed while following the movementof the person in the embodiments, the specific object is not restrictedto a person. A moving object (e.g., an automobile or an animal) otherthan the person may be employed.

(3) Although the distance information is used for detecting the specificobject in the embodiments, means for detecting the specific object isnot restricted thereto. In place of the distance detector 230, it isalso possible to use an imaging device capable of performing imagingthrough RGB light. It is also possible to detect the specific objectfrom an image captured by the imaging device, and furthermore, to detectthe position of the specific object.

(4) It is possible to properly combine the techniques disclosed in thefirst to third embodiments.

As described above, the embodiments have been described as illustrativefor the technique in the present disclosure. For this purpose, theaccompanying drawings and the detailed description have been provided.

Accordingly, the components described in the accompanying drawings andthe detailed description may include components which are indispensableto solve the problems as well as components which are not indispensableto solve the problems in order to illustrate the technique. For thisreason, the non-indispensable components should not be approved to beindispensable immediately based on the description of thenon-indispensable components in the accompanying drawings or thedetailed description.

Moreover, the embodiments serve to illustrate the technique in thepresent disclosure. Therefore, various changes, replacements, additions,omissions, and the like can be made within the claims or equivalentsthereof.

INDUSTRIAL APPLICABILITY

The projecting device according to the present disclosure can be appliedvarious uses for projecting a video onto a projection surface.

What is claimed is:
 1. A projecting device comprising: a projectorconfigured to project a projection image including a content image ontoa projection surface; a first detector configured to detect a targetposition on the projection surface at which the content image is to beprojected; an image processor configured to generate the projectionimage; a driver configured to change an orientation of the projector inorder to change a projection position of the projection image; acontroller configured to control the image processor and the driver,wherein the controller controls the image processor to set a position ofthe content image included in the projection image in order to minimizea difference between a display position of the content image on theprojection surface and the target position when the projection image isprojected in a state in which the orientation of the projector is setsuch that an optical axis of the projector is orthogonal to theprojection surface, and the controller controls the driver to set theorientation of the projector in order to project, at the target positionon the projection surface, the projection image including the contentimage at the set position.
 2. The projecting device according to claim1, wherein the controller includes: a shift direction calculation unitconfigured to calculate, as a shift direction of the content imageincluded in the projection image, a direction from an intersection pointof the optical axis with the projection surface toward the targetposition in a state in which the orientation of the projector is setsuch that the optical axis of the projector is orthogonal to theprojection surface; a shift amount calculation unit configured tocalculate a shift amount of the content image included in the projectionimage, based on the shift direction and a projection angle of view ofthe projector; and a display position determination unit configured todetermine a position of the content image included in the projectionimage, based on the shift direction and the shift amount.
 3. Theprojecting device according to claim 2, further comprising: a storageconfigured to store a display size of the content image, wherein theshift amount calculation unit calculates the shift amount based on thedisplay size.
 4. The projecting device according to claim 2, furthercomprising: a storage configured to store the content image as a binaryimage indicating a display portion and a non-display portion by twovalues, wherein the shift amount calculation unit calculates the shiftamount, based on a shape of the display portion of the binary image. 5.The projecting device according to claim 2, further comprising: a seconddetector configured to detect the content image as a binary imageindicating a display portion and a non-display portion by two values,wherein the shift amount calculation unit calculates the shift amountbased on a shape of the display portion of the binary image.
 6. Theprojecting device according to claim 5, wherein the second detectordetects, as the non-display portion, a pixel having a predeterminedcolor in the content image and detects, as the display portion, a pixelhaving a color other than the predetermined color in the content image.7. The projecting device according to claim 1, wherein the controllerincludes a projecting direction calculation unit configured to calculatean orientation of the projector, based on a difference between thetarget position and the display position.
 8. The projecting deviceaccording to claim 1, wherein the controller includes: a focus distancecalculation unit configured to calculate a focus distance based on aprojection distance from the projector to the target position and anangle formed by an optical axis of the projector and a direction of thecontent image seen from the projector; and a focus control unitconfigured to control a focus of the projector based on the focusdistance.
 9. The projecting device according to claim 1, wherein thecontroller includes: a focus distance calculation unit configured tocalculate a focus distance based on a projection distance from theprojector to the target position, a projection angle of view of theprojector, and the target position in the projection image; and a focuscontrol unit configured to control a focus of the projector based on thefocus distance.
 10. The projecting device according to claim 8, whereinthe controller further includes a preferential position determinationunit configured to determine a preferential position to bepreferentially focused in the content image, and the focus distancecalculation unit calculates a focus distance based on a projectiondistance from the projector to the preferential position and the angleformed by the optical axis of the projector and the direction of thecontent image seen from the projector.
 11. The projecting deviceaccording to claim 9, wherein the controller further includes apreferential position determination unit configured to determine apreferential position to be preferentially focused in the content image,and the focus distance calculation unit calculates a focus distancebased on a projection distance from the projector to the preferentialposition, the projection angle of view of the projector, and thepreferential position in the projection image.
 12. The projecting deviceaccording to claim 10, further comprising: a storage configured topreviously store a position at which focusing is preferentiallyperformed in the content image, wherein the preferential positiondetermination unit determines the position stored in the storage as thepreferential position.
 13. The projecting device according to claim 10,further comprising: a third detector configured to detect a positiongazed in the content image by a gazer, wherein the preferential positiondetermination unit determines a position detected by the third detectoras the preferential position.